Through the development and maintenance of several serially transplantable GBM tumor lines, each of which has been or will be characterized for GBM signature lesions, the Xenograft Core will provide to SPORE investigators robust animal models that recapitulate the invasiveness seen in the human phenotype. The serially passaged xenografts provide a more clinically relevant model than established cell lines grown as xenografts. This determination has many implications for neuro-oncology research, but is likely to be of greatest importance to the testing of experimental therapeutics. It is our contention that results from testing anti-tumor therapeutics with serially-transplanted GBM xenografts will show improved consistency with clinical trial results in humans. Specifically, the Xenograft Core will: 1: Initiate, passage, and archive xenograft tumors derived from Mayo glioma patients. 2: Provide detailed molecular characterization of each xenograft upon establishment and monitor for retention of characteristics. 3: Collect, process, and distribute within and outside Mayo, paraffin-embedded xenograft tumor tissues, serum/plasma, DNA, RNA, and protein. 4: Coordinate and conduct all in vivo therapeutics testing, including NMR image analysis of intracranial xenografts as needed to assess tumor response to therapy. 5: Maintain up-to-date records on all xenograft tissues and related biospecimens. All specimens will be collected and processed under tight quality control, and will be distributed to SPORE researchers or banked for future SPORE research projects. The SPORE Pathology Core will assure that specimens are properly fixed, stained, and histologically evaluated. All activities will be tracked in the Biostatistics Core using a sophisticated database essential to the SPORE. This database merges the activities at Mayo, and allows integration with clinical and other data collected in research projects.